This proposal is for a competitive renewal of the University of Rochester Alzheimer's Disease Center (ADC). This Center is just starting its fourth year of existence. The ADC was preceded by a Program directed at morphological, neurochemical and molecular studies of AD and normal control human brain. These four years have been a time of transition from the program project structure which was oriented around providing well characterized human brains for a limited stet of basic neurobiological studies to the broader scope of an ADC. This ADC contains four cores; 1) Administrative, including Pilot Projects, 2) Clinical, including two satellite Diagnostic & Treatment Centers (SDTC - one Urban and one Rural), 3) Neuropathology and Brain Bank and 4) Education & Information Transfer. The Center Director reports to the Dean, School of medicine and Dentistry. The Core Directors report to the Director and Associate Director of the ADC. The ADC represents a successful and meaningful cooperative effort among a number of departments of the University of Rochester Medical Center, affiliated hospitals, clinics, regional hospitals, area nursing homes and community service organizations, all directed at occasioning cases to the ADC. A major aspect of the transition from program project to ADC has resolved around broadening the base from which patients will be drawn, both through the SDTCs as well as through expansion of the sites monitored by the Clinical Core. Another aspect of the transition has been the addition of a neurological disease control group - multi-infarct dementia. In addition, the ADC is designed to serve a broader range of studies, particularly into the area of clinical studies and trials of therapeutic interventions. The neuropathologic examination of brains has been broadened, particularly to distinguish lewy bodies and plaque subtypes. In addition, the Neuropathology Core proposed to provide randomly sampled counts of senile plaques and neurofibrillary tangles from selected brain regions for correlation with basic science studies. These counts will be in addition to counts obtained for the Khachaturian diagnostic criteria.